• Journal of Life Science
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• v.13 no.4
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• pp.505-510
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• 2003

The extremely halophilic archaebacteriurn Haloarcular sp. EH-1 was isolated from solar salts. Halophages found in Haloarcular sp. EH-1 were isolated from fermented anchovy sauce. Halophages were isolated from fermented anchovy sauce using Haloarcular sp. EH-1 as a host bacterium. The isolated halophage produced 0.5∼l.0 mm in diameter clear plaques. The halophage consists of an symmetrical head, measuring 68 nm in diameter, and a contractile tail, 100 nm long and base plates were observed. Total size of phage DNA genome obtained 20 Kbp and its sequence homology was 52.87% with H. Salinarium.

• Journal of Radiation Industry
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• v.8 no.2
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• pp.105-109
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• 2014

This study was conducted to investigate the sensitivity of Arthrobacter sp. PAMC 25486 to various mutagens. ${\gamma}-ray$, UV-ray, Ethyl methane sulfonate (EMS) and hydrogen peroxide ($H_2O_2$) were used as mutagen, and the survival rate of Arthrobacter sp. was measured at various doses of ${\gamma}-ray$ and UV-ray, and concentrations of EMS and $H_2O_2$. Decimal reduction dose ($D_{10}$ value) of Arthrobacter sp. was determined 370 Gy for a gamma irradiation treatment, 0.019 J for a UV ray, 2.5 mM for EMS, and 230 mM for $H_2O_2$. This result will be applied for the development of superior mutant strain of Arctic bacteria producing valuable compounds.

• Animal Systematics, Evolution and Diversity
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• v.33 no.2
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• pp.73-99
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• 2017

Six new species of siphonostomatoid copepods are described from sponges collected in the Philippines and Vietnam. Two new genera of Asterocheridae, Andapontius and Holobinus, are proposed. The new species are Andapontius granulatus n. gen. n. sp., Holobinus angustus n. gen. n. sp. and Dermatomyzon boxshalli n. sp. in the family Asterocheridae and Entomopsyllus brevicaudatus n. sp., Paralepeopsyllus leei n. sp. and P. dambayensis n. sp. in the family Entomolepididae. Doropontius denticornis Thompson and Scott, 1903, is redescribed for the first time since its original record.

• Mycobiology
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• v.49 no.5
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• pp.521-526
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• 2021

Three isolates belonging to the ascomycetous genus Zygotorulaspora were obtained from the fruits of Cornus officinalis and Smilax china, and flowers of Dendranthema zawadskii var. latilobum in Gongju-si, Korea. Phylogenetic Analyses of the LSU D1/D2 domain and ITS region sequences supported the recognition of two new species: Zygotorulaspora cornina sp. nov. (type strain NIBRFGC000500475 = KACC93346P^PP) and Zygotorulaspora smilacis sp. nov. (type strain NIBRFGC000500476 = KACC93347P^PP). The two novel species revealed no growth on D-Galactose, unlike the other six species in the genus Zygotorulaspora. They are distinguished from each other by their phylogenetic differences and phenotypic characteristics such as assimilation of xylitol, 5-keto-D-gluconate, and ethanol. All species in the genus Zygotorulaspora including the two novel species have phenotypic traits of genus Zygotorulaspora: asci are persistent, sucrose and raffinose are assimilated, and m-inositol is not required for growth, and they are mainly associated with plants.

• Journal of Microbiology and Biotechnology
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• v.31 no.4
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• pp.493-500
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• 2021

Endophytic fungi are symbiotically related to plants and spend most of their life cycle within them. In nature, they have a crucial role in plant micro-ecosystem. They are harnessed for their bioactive compounds to counter human health problems and diseases. Endophytic Diaporthe sp. is a widely distributed fungal genus that has garnered much interest within the scientific community. A substantial number of secondary metabolites have been detected from Diaporthe sp. inhabited in various plants. As such, this minireview highlights the potential of Diaporthe sp. as a rich source of bioactive compounds by emphasizing on their diverse chemical entities and potent biological properties. The bioactive compounds produced are of significant importance to act as new lead compounds for drug discovery and development.

• Bulletin of the Korean Mathematical Society
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• v.60 no.1
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• pp.33-46
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• 2023

Geodesic orbit spaces are homogeneous Finsler spaces whose geodesics are all orbits of one-parameter subgroups of isometries. Such Finsler spaces have vanishing S-curvature and hold the Bishop-Gromov volume comparison theorem. In this paper, we obtain a complete description of invariant (α₁, α₂)-metrics on spheres with vanishing S-curvature. Also, we give a description of invariant geodesic orbit (α₁, α₂)-metrics on spheres. We mainly show that a Sp(n + 1)-invariant (α₁, α2)-metric on S⁴ⁿ⁺³ = Sp(n + 1)/Sp(n) is geodesic orbit with respect to Sp(n + 1) if and only if it is Sp(n + 1)Sp(1)-invariant. As an interesting consequence, we find infinitely many Finsler spheres with vanishing S-curvature which are not geodesic orbit spaces.

• The Korean Journal of Mycology
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• v.51 no.4
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• pp.361-371
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• 2023

The study was undertaken to isolate and characterize wild yeast strains from soil samples collected in Seoul, Korea. Among the 19 yeast strains obtained, 17 were previously recorded species. The remaining two strains, Wickerhamomyces sp. GW1-4 and Archaeorhizomyces sp. YB4-103 were new species candidates. The genomic and microbiological characteristics of GW1-4 and YB4-103 were investigated. Phylogenetic analyses based on the 26S rRNA gene sequences and internal transcribed sequences, GW1-4 and YB4-103, represent a distinct lineage within the family Phaffomycetaceae and Archaeorhizomycetaceae, respectively. The GW1-4 and YB4-103 strains had the highest sequence homology with Wickerhamomyces xylosivorus NBRC 111553^T (88.97%) and Archaeorhizomyces finlayi CBS 128710^T (87.55%), respectively.

• Korean Journal of Microbiology
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• v.35 no.2
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• pp.139-145
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• 1999

Aromatic hydrocarbons which are not easily degraded by microorganisms can be accumulated in the conlaminated environment for a long lime, producing toxic effects on wild lives and humans. However, the sublethal concentrations of the chemicals induce the synthesis of stress-shock proteins in the cells and increase the adaptability of the organisms to the environmental stresses. In this study, therefore, the cells of Psezido~nonus sp. DJ- 12 treated with catechol at various concentrations were inveshgated for their survival, biodegtadability of catechol, production of stress-shock proteins, and cytological changes. The organisms were capable of degrading catechol at the range of 0.5 to 1.0 mM concentration wilhin 6 hours incubation, but they were killed by $10^2$-10$^3$ celllinl at 3 mM or higel- concentration without any catechol degradation. These cells treated with catechol begm lo produce DnaK and GroEL at 1 mM and 0.5 mM. respectively. Pseudumonas sp. DJ-12 treated with 10 mM catechol for I hour exhihiled some punctuated pores on the cell wall and contortion of the rod shape. The cells treated with he sublethal concentration of catechol showed the increased tolerance for suvival when exposed to the lethal concentration, and such tolerant effects were functioned crossly among benzoate, 4-chlorobenzoate, 'and catechol.

• Korean Journal of Microbiology
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• v.40 no.2
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• pp.139-146
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• 2004

A bacterium producing alkaline cellulase was isolated from soil, leaf mold and compost, and was identified as alkalophilic Bacillus sp. HSH-810 by morphological, cultural and biochemical determination. The optimum cul-ture condition of Bacillus sp. HSH-810 for the growth and alkaline cellulase production was $30^{\circ}C$ and pH 10.0. The maximum alkaline cellulase production was obtained when 1.0%(w/v) CMC, 0.5%(w/v) peptone, 0.02%(w/v) $CaCl_2$ and 0.02(w/v) $CoCl_2$ were used as carbon source, nitrogen source and mineral source, respectively. The optimum pH and temperature of the enzyme activity were pH 10.5 and $50^{\circ}C$, respectively. This enzyme was fairly stable in the pH range of 6.0-13.0 and at $50^{\circ}C$. For the effect of surfactants, the activity of alkaline cellulase was stable in the presence of sodium-$\alpha$-olefin sulfonate (AOS), sodium dodecyl sulfonate (SDS), Tween 20 and Tween 80, but inhibited by the presence of 0.1 linear alkyl-benzene sulfonate (LAS) sig-nificantly.

• Microbiology and Biotechnology Letters
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• v.18 no.6
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• pp.633-639
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• 1990

The genes for cellulases of Pseudomonas sp. LBC505 and CYC10, potent cellulase complex-producing strains, were cloned in Escherichia coli with pUC19. Recombinant plasmids pLCl and pLC2 were isolated from transformants producing cellulase by Congo red staining, and their genes cloned were 0.7 kb and 4.6 kb HindIII fragments, respectively. The inserts of pLCl and pLC2 were hybridized to chromosomal DNAs digested with HindIII from Pseudomona~ sp. LBC505 and CYC10, respectively. Immunodiffusion assays revealed that pLC1-and pLC2-encoded cellulase showed similarity with that of host strains. About 24% of cellulase activity was observed in the extracellular fraction of E. coli carrying pLC1, and its activity was higher about 1.4 times than that of LBC505. The enzymatic properties of pLC1 and pLC2 encoded cellulase were the same as those of cellulase from host strains. HPLC analysis and substrate specificity showed that cellulases were the same as those of cellulase from host strains. HPLC analysis and substrate specificity showed that cellulases cloned were endocellulase.